A kind of renovation process of powdered activated carbon
Technical field
The present invention relates to a kind of waste active carbon regeneration techniques, be specifically related to a kind of renovation process of powdered activated carbon.
Background technology
Caffeine belongs to the xanthine alkaloid compound, is a kind of central nervous excitation agent, and is because the medicine of main component is used to treat neurasthenia and symptoms such as spirit inhibition, headache, respond well with coffee, is widely used on the market now.In the caffeine production process, adopting urea, monomethyl amine and monoxone is the dimethyl urea synthetic route of base stock.In the production process, adopt active carbon that the synthetic bullion caffeine aqueous solution is carried out decolorizing and refining, when removing pigment and other impurity, also adsorbed a large amount of caffeines, produced the waste active carbon of year caffeine thus.The annual discharge capacity of this waste active carbon reaches 2000 tons, wherein contains 20% caffeine.
Because of it dissolves in chloroform, former process using be that chloroform extraction reclaims caffeine, exist the medicament loss big in the processing procedure, problems such as medicament strong toxicity; And the active carbon that removes caffeine adopts burning method to handle at present, not only causes the wasting of resources of high added value caffeine and active carbon, and burn to produce toxic and harmfuls such as a large amount of CO2 and nitrogen oxide, oxysulfide, has polluted environment.Therefore, exploitation is a kind of reclaims caffeine and makes the method and technology of regeneration of activated carbon significant from carry the caffeine active carbon.
At present, the regeneration of activated carbon technology of using in the industry mainly contains following several kinds: the chemical method of medicament wash-out, bio-regeneration method, wet oxidation process, electrolytic oxidation and thermal regeneration method.The temperature of in heating process, decomposing desorption according to adsorbed organic matter in the active carbon is different, and the thermal regeneration method can be divided into low-temperature heat regeneration and heat regeneration, but effect is not very good.
Summary of the invention
The present invention overcomes the deficiency of prior art; A kind of method of utilizing method of reproduction to handle effective decolorizer regeneration of load caffeine in the exquisite process of caffeine has been proposed; Two sections gradient-heated of said method exploitation reclaim caffeine and regeneration of activated carbon comprehensive resource technology continuously; Have the advantages that production process is continuous, the caffeine capturing efficiency is high, the regeneration of activated carbon rate is high; The regeneration and the resource of waste active carbon when effectively reclaiming caffeine, have also been realized, the CO2 emission of having avoided the waste active carbon burning to form.
Technical scheme of the present invention is: continuously through one-level regenerating furnace, secondary regenerating furnace, spray column and condenser, the temperature control through strict realizes the regeneration of active carbon with waste active carbon for a kind of renovation process of powdered activated carbon, said method, and concrete steps are:
1) temperature rises to more than 100 ℃ in the one-level regenerating furnace, when secondary regenerating furnace temperature rises to more than 400 ℃, waste active carbon is added in the one-level regenerating furnace continuously.
2) the one-level regenerating furnace makes the water evaporation of absorption in the carbon granule, and the lower boiling organic matter of part also evaporates thereupon simultaneously, and temperature maintenance is at 100~130 ℃, and this part water vapour reclaims behind condenser.
3) active carbon after the dehydration gets in the secondary regenerating furnace, and it is the nitrogen of 0.005~0.007m/s that the secondary regenerating furnace feeds linear velocity, and temperature maintenance is in 420~450 ℃ of scopes; After caffeine distillation this moment; Taken out of by nitrogen, pigment decomposes simultaneously, and active carbon obtains regeneration.
4) for preventing that caffeine gas from condensing, the caffeine pipeline is auxilliary to have the companion hot, behind the entering spray column, captures with aqueous solution caffeine spray.
In the above-mentioned steps 1, the waste active carbon content of caffeine is 10~25%
In the above-mentioned steps 2, the active carbon water content after the dehydration is 5~8%.
In the above-mentioned steps 3, the regeneration of activated carbon rate is 90~93%.
In the above-mentioned steps 4, aqueous solution caffeine concentration is 0~0.25g/mL, and temperature is 20~80 ℃, and the caffeine capture rate is 96~100%.
The present invention has following beneficial effect
Two sections gradient-heated that the present invention relates to reclaim caffeine and regeneration of activated carbon comprehensive resource technology continuously; Have the advantages that production process is continuous, the caffeine capturing efficiency is high, the regeneration of activated carbon rate is high; The regeneration and the resource of waste active carbon when effectively reclaiming caffeine, have also been realized, the CO2 emission of having avoided the waste active carbon burning to form.
Description of drawings
Accompanying drawing is a schematic flow sheet of the present invention.
Among the figure, 1, the one-level regenerating furnace; 2, secondary regenerating furnace; 3, condenser; 4, spray column.
The specific embodiment
Said referring to accompanying drawing, continuously through one-level regenerating furnace 1, secondary regenerating furnace 2, spray column 4 and condenser 3, the temperature control through strict realizes the regeneration of active carbon with waste active carbon in the present invention.
Embodiment 1
Treat that temperature rises to 100 ℃ in the one-level regenerating furnace, secondary regenerating furnace temperature rises to 400 ℃, will carry the caffeine active carbon and add in the one-level regenerating furnace by adding speed 0.9t/h.Treat that the active carbon water content reduces to 8%, the active carbon after the dehydration is advanced in the secondary regenerating furnace, and nitrogen gas speed is 0.007m/s, this stage caffeine distillation, and pigment decomposes.Caffeine after the distillation gets into spray column and captures recovery, and the caffeine rate of recovery is 98%, and the regeneration of activated carbon rate is 88%.
Embodiment 2
Treat that temperature rises to 100 ℃ in the one-level regenerating furnace, secondary regenerating furnace temperature rises to 400 ℃, will carry the caffeine active carbon and add in the one-level regenerating furnace by adding speed 0.6t/h.Treat that the active carbon water content reduces to 6%, the active carbon after the dehydration is advanced in the secondary regenerating furnace, and nitrogen gas speed is 0.006m/s, this stage caffeine distillation, and pigment decomposes.Caffeine after the distillation gets into spray column and captures recovery, and the caffeine rate of recovery is 98.5%, and the regeneration of activated carbon rate is 89%.
Embodiment 3
Treat that temperature rises to 105 ℃ in the one-level regenerating furnace, secondary regenerating furnace temperature rises to 420 ℃, will carry the caffeine active carbon and add in the one-level regenerating furnace by adding speed 0.5t/h.Treat that the active carbon water content reduces to 5%, the active carbon after the dehydration is advanced in the secondary regenerating furnace, and nitrogen gas speed is 0.005m/s, this stage caffeine distillation, and pigment decomposes.Caffeine after the distillation gets into spray column and captures recovery, and the caffeine rate of recovery is 98%, and the regeneration of activated carbon rate is 90%.
Embodiment 4
Treat that temperature rises to 100 ℃ in the one-level regenerating furnace, secondary regenerating furnace temperature rises to 400 ℃, will carry the caffeine active carbon and add in the one-level regenerating furnace by adding speed 0.5t/h.Treat that the active carbon water content reduces to 6%, the active carbon after the dehydration is advanced in the secondary regenerating furnace, and nitrogen gas speed is 0.007m/s, this stage caffeine distillation, and pigment decomposes.Caffeine after the distillation gets into spray column and captures recovery, and the caffeine rate of recovery is 97%, and the regeneration of activated carbon rate is 90%.
Embodiment 5
Treat that temperature rises to 100 ℃ in the one-level regenerating furnace, secondary regenerating furnace temperature rises to 410 ℃, will carry the caffeine active carbon and add in the one-level regenerating furnace by adding speed 0.6t/h.Treat that the active carbon water content reduces to 8%, the active carbon after the dehydration is advanced in the secondary regenerating furnace, and nitrogen gas speed is 0.006m/s, this stage caffeine distillation, and pigment decomposes.Caffeine after the distillation gets into spray column and captures recovery, and the caffeine rate of recovery is 97.5%, and the regeneration of activated carbon rate is 89%.